It’s November in a very dry year which was preceded by a dry year. Most native plants are waiting for the rains. The small amount of rain that fell in the last week in October I doubt will be considered significant, i.e., sufficient enough to initiate plant growth. So Bonnie and I have punted on the selection of the plant profiled in this issue of the Obispoensis. We have chosen to make a scan of an all too common grass which is generally known as Bermuda grass, Cynodon dactylon.
According to Wikipedia, it has lots of common names in many different languages. Gardeners often refer to it as devil grass when in mixed company. I suspect they use more colorful language when they are trying to eliminate it from their lawns and gardens. The common name, Bermuda grass, reminds us not to depend on names to give us accurate information. Yes, Bermuda grass does grow in Bermuda, but it also grows throughout the warmer parts of the world. It grows on every continent that has areas where periods of low temperatures are rare or of very short duration. In the U.S. it is found in almost every one of the lower 48 states. It is especially common in the warmer half of the country.
Where does Bermuda grass come from if not Bermuda? It has at least three other wild varieties and all of them, including the wide-spread variety, Cynodon dactylon var. dactylon, are found in South-East Africa. Only C. d. var. dactylon has a worldwide distribution.
It was probably introduced to the U.S. in the 18th century, whether as a lawn grass or for forage crop is not clear. The species is able to survive long periods of drought by simply “dying back” to its extensive net-like system of rhizomes (horizontal underground stems). Aerial shoots can arise from any of its multitude of nodes (region of stems that produce leaves and buds). It is this capability to form long and extensively branched rhizomes that explains its use as a lawn grass. However, its weakness is its habit dying back during drought. This means that one’s nice green lawn will have brown spots or, if a Bermuda grass lawn, turn completely brown during the dry season.
Bermuda grass also doesn’t share an area well — it is extremely aggressive. In experiments where Bermuda grass is grown with various other herbaceous species, it inhibits the other species. In some cases Bermuda grass growth is better when paired with other species than when it grows alone. Needless to add, its aggressive growth is why gardeners refer to it as devil grass.
Where there is adequate water, Bermuda grass puts much of its growth into its green aerial shoots which makes it an almost great pasture grass. Why “almost great?” It is because, under some environmental conditions, livestock poisoning has been traced to it. The species is a prolific pollen producer so it is a major cause of discomfort by allergy and asthma sufferers.
I hope it goes without saying that Bermuda grass is not a California native and must be considered a noxious weed! It is most common in disturbed, vacant lots and poorly maintained lawns throughout the human dominated portions of our chapter area. It can also be found on roadsides and dryer edges of streams and salt marshes or wherever woody plants are widely scattered. It does seem to behave itself because it doesn’t seem to compete against trees and shrubs very well. It does not spread into native plant areas as it is intolerant of shade.
The scientific name, Cynodon, is derived from Greek and means “dog tooth.” The dog teeth are the distinctive small scale-like leaves that arise from the nodes of the rhizomes. Dactylon is also from Greek and refers to finger- like structures. In this case it refers to the usually 4 or 5 thin inflorescence branches which somewhat resemble the fingers of a human hand with the fingers widely separated.